1. Field
The present disclosure relates generally to light bulbs and lamp assemblies, and more particularly, to a light emitting diode (LED) based light engine that can replace a conventional PAR30 or PAR20 incandescent bulb used in outdoor/exterior light fixtures with no modifications to the host lighting fixture.
2. Description of the Related Art
Incandescent light bulbs are used in a large variety of lighting products. Although inexpensive to purchase, incandescent light bulbs have several drawbacks. First, incandescent light bulbs use a relatively large amount of power compared to other lighting products which increase energy costs. Second, incandescent light bulbs have a short life causing repetitive replacement costs. Furthermore, since theses bulbs have a short life, labor costs will subsequently be effected by having maintenance personnel constantly replace the bulbs.
Recently, a trend in the lighting industry is to develop light emitting diode (LED) light modules that can be easily adapted to current light fixture products. LED technology offers more than twice the energy efficiency of traditional incandescent bulbs and has 20-30 times the reliability. This offers a potentially large savings in energy in outdoor/exterior applications, where many PAR30/PAR20 bulbs are used today. While LED technology is generally more expensive, there can be a substantial savings in bulb replacement and maintenance costs over a 5-year or greater life-cycle.
To-date, most LED based light bulbs that are intended to replace traditional light bulbs use a large number of low power LEDs (e.g., 5 mm or 20 mA surface mount LEDs) to produce the required light output. This approach has an advantage of simplifying the electronics, since large strings of LEDs can have a voltage drop that is closely matched to the source voltage (e.g. 120 VAC). The disadvantages with this approach are that the 5 mm LEDs do not offer the same service life as higher power LEDs, large quantities of 20 mA surface mount LEDs are more expensive than using fewer high power LEDs, and the light pattern produced is more difficult to control when using a wide area light source (i.e. a large array of LEDs make it more difficult to produce a narrow spotlight).
Thus, a need exists for an LED lighting product having low power consumption and long life. Furthermore, a need exists for an LED based light engine that can be a drop-in/screw-in replacement for a PAR30/PAR20 bulb, wherein the light engine can be easily retrofitted into existing light fixtures at residential and commercial installations.